NPT 101: Which countries have nuclear weapons?

The Non-Proliferation Treaty was designed to limit the acquisition of nuclear weapons to five countries who already had them. But now four more states have joined the nuclear club – an 'erosion' of the treaty that could spell its doom.

Five signatories to the Non-Proliferation Treaty, or NPT, have nuclear weapons: the US, Russia, China, France, and Britain. Of those, the US and Russia control the vast majority of the world's nuclear warheads.

Yet three non-NPT members – Israel, India, and Pakistan – have all secretly developed nukes and suffered little consequence. North Korea, a former signatory, took advantage of a loophole in the treaty, pulling out in 2003 and testing nuclear weapons.

Iran, which Western powers suspect of developing nuclear weapons, lies at the nexus of the NPT’s declared rights and obligations, and will be a key talking point at the NPT Review Conference held May 3-28 in New York.

Israel in 2007 attacked a facility in Syria it said was a budding nuclear plant, notes Ms. Goldring. Pakistan is also not an NPT member, but is under threat from Sunni militants, and could feel the need to boost its nuclear arsenal to match India – another non-NPT member that is nevertheless engaged in big-ticket deals with the US and other weapons states.

There is a “drip, drip, drip” erosion, Goldring says, a “debilitating effect on the [nonproliferation] regime with each of these announcements. It decreases the power of the regime for those who are inside, and decreases the incentives for those who are outside to want to be inside.”